Shower stool



FIG. 1 is a top perspective view of the shower stool;

FIG. 2 is a top view of the shower stool; and,

FIG. 3 is a side view of the shower stool.

Broken lines shown in the drawings are for illustrative purposes only and form no part of the claimed design. 

CLAIM The ornamental design for a shower stool, as shown and described. 